Method of amplifying a beneficial selective skin response to light energy

ABSTRACT

A method of altering the appearance of a region of skin is disclosed. The method includes applying a sensitizing wavelength of light the region, and applying a treatment wavelength of light to the skin, wherein the treatment wavelength is a shorter wavelength than the sensitizing wavelength. The application of the sensitizing wavelength of light and the treatment wavelength of light results in a change in a physical property of the skin.

PRIORITY CLAIM

[0001] This is a continuation of U.S. Pat. application Ser. No.10/024,270, filed Dec. 17, 2001, which claims the benefit of U.S.Provisional Patent Application No. 60/256,555, filed Dec. 18, 2000, andU.S. Provisional Patent Application No. 60/258,006, filed Dec. 20, 2000,all of which are incorporated by reference herein.

FIELD OF THE INVENTION

[0002] This invention relates to the field of skin treatment, morespecifically to the use of light to change the appearance of the skin.

BACKGROUND OF THE INVENTION

[0003] As light energy is absorbed within the skin, light can be used toachieve desired clinical results. In particular, light has been used toremove hair, eliminate leg veins, remove or reduce the color of tattoos.In addition, water absorption of light energy transforming light intoheat energy has been used for laser ablation of the skin surface or foruse of lasers as cutting instruments. Plastic surgeons, dermatologistsand their patients continually search for new and improved methods toalter the appearance of the skin.

[0004] Presently, all of the methods using either lasers or intensepulsed light in treating the skin require that the emitted energy to beabsorbed selectively within the skin. The object that absorbs thatenergy, is termed a chromophore. The chromophore can be a true colorsuch as black or brown, or red. Alternatively, this is a moleculeabsorbing energy, such as water or protein complex. Selectivechromophore absorption is the absorption of a particular type of lightenergy by a chromophore. A clinical treatment can work because ofselective chromophore absorption, wherein light energy is selectivelyabsorbed by a particular component of the skin. If light energy werenon-selectively absorbed throughout the skin, damage and injury wouldoccur. The current problem in present laser and intense light treatmentof the skin is that the clinical gain is often limited because theamount of beneficial skin selective chromophore absorption is alwayslimited by the amount of non-selective unwanted absorption of energythroughout the skin.

SUMMARY OF THE INVENTION

[0005] The foregoing and other objects, features, and advantages of theinvention will become more apparent from the following detaileddescription of a several embodiments which proceeds with reference tothe accompanying figures.

[0006] A method of altering the appearance of a region of skin isdisclosed. The method includes applying an effective amount ofsensitizing wavelength of light to the region, and applying an effectiveamount of a treatment wavelength of light to the region, wherein thetreatment wavelength is a shorter wavelength than the sensitizingwavelength. The application of the effective amount of the sensitizingwavelength of light and the effective amount of the treatment wavelengthof light results in a change in a physical property of the skin.

[0007] In one embodiment, a method of beneficially altering theappearance of a region of skin is disclosed. The method includesapplying sequenced complementary pulses of light energy, emitted from alaser or intense pulsed light source, to chromophore targets in theskin. There is a synergistic amplification of clinical response thatresults in a change in a physical property of the skin.

BRIEF DESCRIPTION OF THE FIGURES

[0008]FIG. 1 is a schematic representation of the outermost layers ofmammalian skin.

[0009]FIG. 2 is a schematic representation of a first pulse of infraredlaser light. The light energy is absorbed by water molecules within thecollagen layer of the skin. The pulse of infrared light energy reachesdeeper into the skin than pulsed visible light or visible laser light.

[0010]FIG. 3 is a schematic representation of transfer of this energyfrom the first infrared laser pulse into heat and blood vesselenlargement thereby increasing the size of smaller and deeper bloodvessels in the collagen level of the skin.

[0011]FIG. 4 is a schematic representation of a pulse of visible lightenergy on the skin. The energy can be emitted either from a laser orintense pulsed light source. This light energy reaches into the collagenlevel of the skin and is captured by smaller blood vessels, which wereaugmented by a first infrared light energy pulse.

[0012]FIG. 5 is a schematic representation of the outermost layers ofmammalian skin, including a hair and a hair gland within the skin, withsurrounding smaller blood vessels that nourish the hair gland.

[0013]FIG. 6 is a schematic representation showing a primary first pulseof light energy from either a laser or intense pulsed light source thatpenetrates into the skin and is absorbed by the pigment chromophorewithin the hair gland.

[0014]FIG. 7 is a schematic representation which shows the energy fromthe first laser pulse, which absorbed by the pigment within the hairgland, being transmitted as heat energy to the surrounding small bloodvessels. These blood vessels are too small to be seen selectively bypulsed visible light.

[0015]FIG. 8 is a schematic representation which shows how the effectsare amplified by a subsequent pulse of visible light energy that is nottargeting hair pigment or the hair gland directly, but is destroying thesmaller blood vessels around the hair gland.

[0016]FIG. 9 is a bar graph showing the overall ratings of improvementin the skin with a first laser light pulse, followed by a subsequentpulse of visible light energy. Results shown are a rating by treatedindividuals, using defined parameters.

[0017]FIG. 10 is a bar graph showing the percent of improvement of finelines and wrinkles responding to treatment. Results shown are a ratingby treated individuals, using defined parameters.

[0018]FIG. 11 is a bar graph showing the percent of improvement ofrosacea. Results shown are a rating by treated individuals, usingdefined parameters.

[0019]FIG. 12 is a bar graph showing the percent of improvement of blushtone. Results shown are a rating by treated individuals, using definedparameters.

[0020]FIG. 13 is a bar graph showing the percent of improvement offacial blood vessels. Results shown are a rating by treated individuals,using defined parameters.

[0021]FIG. 14 is a bar graph showing the percent of improvement of skinroughness. Results shown are a rating by treated individuals, usingdefined parameters.

[0022]FIG. 15 is a bar graph showing the percent of improvement of skincolor. Results shown are a rating by treated individuals, using definedparameters.

[0023]FIG. 16 is a bar graph showing the percent of improvement of brownage spots. Results shown are a rating by treated individuals, usingdefined parameters.

[0024]FIG. 17 is a bar graph showing the percent of pore size. Resultsshown are a rating by treated individuals, using defined parameters.

[0025]FIG. 18 is a bar graph showing the combined improvement scores fortreatment of the neck.

[0026]FIG. 19 is a schematic diagram of a device for the treatment ofthe skin that includes a controller 100 that controls two light sources(λ₁ 110 and λ₂ 120). Light emitted from these two light sources isdirected to the skin 140 using an optic system 130.

DETAILED DESCRIPTION OF SEVERAL EMBODIMENTS

[0027] The following disclosure and methods are provided to betterdefine the present invention, and to guide those of ordinary skill inthe art in the practice of the present invention. It must be noted thatas used herein and in the appended claims, the singular forms “a”, “an”,and “the” include plural referents unless the context clearly dictatesotherwise. Thus, for example, reference to “a cell” includes a pluralityof such cells and reference to “the laser” includes reference to one ormore lasers and equivalents thereof known to those skilled in the art,and so forth.

[0028] Unless defined otherwise, all technical and scientific terms usedherein have the same meaning as commonly understood to one of ordinaryskill in the art to which this invention belongs.

[0029] As discussed above, selective chromophore absorption of light canbe limited during treatment of the skin. A chromophore is a chemicalgroup that absorbs light at a specific frequency and so imparts color toa molecule. The reasons for the limitations on selective chromophoreabsorption of light energy are several. A common reason is that thechromophore presents too small of a target surface area so that lightenergy absorption is less than needed for the desired result.Alternatively, a given chromophore target my lie at a greater depthwithin the skin such that light energy is attenuated, thus the lightenergy absorption is less than needed for the desired result. Thedesired result of treatment may be either the elimination of that targetor an inflammatory response elicited by energy absorption of thatchromophore target. If the target chromophore initial response to aninitial irradiance is not sufficient, and the energy absorption of thetargeted chromophore is below a sufficient threshold response, then thedesired biologic response can not be elicited. Irradiance is the densityof radiation incident on a given surface usually expressed in watts persquare centimeter or per square meter.

[0030] A greater target chromophore response is often desired and ofdefinite biologic advantage. However, the present approach in use fortreatment is to simply increase the initial irradiance. The logic ofthis present treatment is that more energy of like wavelength and kinddelivered can reach a progressively smaller and perhaps deeper targetchromophore area. However, the problem with this present approach totreatment is that at greater fluences of energy target specificitybecomes less. As target specificity becomes less there is anincreasingly greater chance of widespread injury in the surrounding skinbecause of nonselective energy absorption (as seen at higherirradiance). Nonselective energy absorption results in thermal injury tothe surrounding tissues with increased risk of actual tissue injury,damage, and scarification (scar formation).

[0031] Thus, a method of amplifying skin and the appearance of the skinis provided by the methods described herein. The textural qualities ofthe skin can be improved, including brightness, clarity, smoothness,porosity, and translucency. Other qualities that can be measured includesmoothness, pore size, telangiectasias, flushing, laxity, and dyschromicpigmentation. Additional and important qualities of the skin that can besubjectively and objectively measured include, but are not limited toskin laxity, or conversely skin tightness, and the presence and degreeof textural fine lines and coarser lines within the skin.

[0032] These are the same qualities by which the external aspects ofappearance (e.g. aging of skin) are judged. Improvement in thesequalities by the method of treatment disclosed herein results in abenefit based on visual judgement of appearance. Changing a quality ofthe skin by the methods disclosed herein lessens the appearance of agingof the skin.

[0033] The methods disclosed herein utilize a sequence of irradiance oflaser and intense pulsed light which are not identical, and are not asimple repetition, but are of irradiance of different nature and arecomplementary and additive in their tissue response. The use of theamplification of selective light energy absorption within the skinresults in an increased benefit from the treatment and lessens the riskof injury by reason of non-selective energy absorption by the skin.

[0034] The sequences of laser and/or intense light disclosed herein areabsorbed by the skin. The light energy is absorbed by the epidermis, thedermis, and/or the underlying hypodermis. Without being bound by theory,the sequence of laser and/or intense light pulses enhances thesusceptibility of a chromophore within the skin or the adjacentconnective tissue. The chromophore may be too small in its primarysurface area, or too deep within the skin, or in its primary nature nothave sufficient chromophore specificity, to achieve the desired effectwith a single wavelength of light is applied. Thus, the enhancedsusceptibility is due to a primary pulse of laser or intense light,termed a sensitizing wavelength of light. Following application of thesensitizing wavelength of light the enhanced target chromophore issusceptible to effective treatment with a second irradiance, termed atreatment wavelength of light. In one embodiment, the treatmentwavelength is complementary intense pulsed light or a complementarylaser pulse. The complementary intense pulsed light or laser pulse byitself, as a primary treatment, does not have sufficient therapeuticefficacy. It is only in combination with the sensitizing wavelength thatthe treatment wavelength is effective. Thus, the sequenced complementarylaser and/or intense pulsed light irradiance amplify the desiredchromophore response within the skin to achieve an enhanced therapeuticresponse.

[0035] The light sources used in the methods of the invention for eithersensitizing irradiation or for amplification of a primary irradiatedchromophore may either be a coherent or a non-coherent light source. Acoherent light source is a source of light that is capable of producingradiation with waves vibrating in phase. The laser is one specific,non-limiting example of a coherent light source. In one embodiment, acoherent light source is an infrared laser, and a non-coherent lightsource is pulsed light that can be filtered (see Bitter, Dermatol. Surg.26:835-843, 2000; Weiss et al. Dermatol. Surg. 26:823-828, 2000; Kelleyet al., Lasers Surg. Med. 95:32-33, 1997).

[0036] Specific non-limiting examples of lasers of use with the methodsdisclosed herein include multiple infrared laser sources, pulsed dyelasers, and intense pulsed light. Infrared laser sources of use include,but are not limited to, the Vasculite laser™ at a wavelength of 1064 nm,the Cool Touch Laser™ (either the CoolTouch I™, see U.S. Pat. No.5,820,626, or the CoolTouch II™, see U.S. Pat. No. 5,967,123, CoolTouchCorporation, Roseville, Calif.) at 1320 and 1540 nm, and the Arameiserbium glass laser, a flash lamp-excited erbium glass laser (1.54 nm),Quantel Medicall, France (U.S. Pat. No. 5,897,549). The pulsed dye lasersources of use with the methods disclosed herein include, but are notlimited to, the Photogenica V™ and V Star™ lasers (e.g. see U.S. Pat.No. 4,364,015 and U.S. Pat. No. 6,045,548, Cynosure, Inc. Chelmsford,Mass.) with use at both 585 and 595 nm. The intense pulsed light sourcesof energy use with the methods disclosed herein include, but are notlimited to, the Photoderm Multilight™ (e.g. see U.S. Pat. No. 5,683,380and U.S. Pat. No. 5,720,772, ESC/Sharplan (Lumenis), Norwood, Mass.)with spectral band of emission of filter intense pulsed light of between515 nm and 1200 nm. In one embodiment, wherein a surface erythemaprimary response by reason of microabrasion is desired, one specific,non-limiting example of a light source of use is the Parisian Peel™microabrasion system.

[0037] The spectral wavelength of coherent light laser sources as usedmay range from short wavelength visible light to extend into the longinfrared wavelengths of about 1520 nanometers or longer. In oneembodiment, the wavelength of the light is a short wavelength, or fromabout 500 nanometers (nm) to about 600 nm. In another embodiment, thewavelength of light is visible light, or from about 400 nm to 700 nm. Inyet another embodiment, the wavelength of light is from about 600 nm toabout 1320 nm, or from about 695 nm to about 1200 namometers.

[0038] In a further embodiment, the wavelength of light is a longwavelength, such as infrared light. Infrared light is light of theinvisible spectrum, consisting of electromagnetic radiation withwavelengths in the range from 750 nanometers to 1 millimeter. Onespecific, non-limiting example of infrared light is light of about 1320nanometers or longer. Another specific, non-limiting example of infraredlight is the use of light emitted from a Nd:YAG laser of 1320nanometers. The use of this spectrum is not limited, but may include aswell shorter wavelength infrared emissions of 1040 nanometers. Withoutbeing bound by theory, this may be less efficient, possibly by reason oflesser diffusional absorption of this energy by water contained withinthe target tissue. In addition, longer wavelength light may as well beuseful, provided that sufficient absorption in depth of the infraredlaser energy is be achieved.

[0039] The pulsewidths used for both coherent and non-coherent lightsources may range from about a nanosecond pulse to a long duration pulseof about 10, about 20, about 30, about 50 or about 100 milliseconds orlonger. Pulsewidth is associated with the effective thermal relaxationtime. In one embodiment, pulsewidth is associated with thecross-sectional dimension of the target chromophore. In addition, one ofskill in the art can readily determine the spectral wavelength of lightand the pulse duration based on the spectral absorption of the targetedchromophore, and the depth of the chromophore within the skin.

[0040] Without being bound by theory, the spectral wavelength of lightis determined by the spectral absorption of the targeted chromophore,and relative depth of that chromophore within the skin itself. Atherapeutically effective amount of light is the amount of lightsufficient to affect, or to alter a property of, the target. One ofskill in the art can readily determine the appropriate spectrum for agiven chromophore, based on the absorption and emission spectrum of thechromophore. Thus, in one specific, non-limiting example, coherent laserlight sources for chromophore amplification are used. Primaryirradiation of the skin is performed with a sensitizing wavelength thattargets a chromophore and prepares the skin for a treatment wavelength.In one embodiment, a sensitizing wavelength is an infrared wavelength.One specific non-limiting example of a sensitizing wavelength is emittedfrom an infrared laser source, of about 1320 nanometers. Without beingbound by theory, shallow surface associated cooling allows for a dermalabsorption of laser energy by reason of water absorption. Thistemperature elevation of the shallow to deeper collagen bearing part ofthe skin, the dermis, vasodilates small, threshold in sizes bloodvessels within the skin. In one embodiment these vessels arecapillaries.

[0041] A closely linked second laser sequence follows, termed thetreatment wavelength. A therapeutically effective amount of thetreatment wavelength provides the desired therapeutic result. In oneembodiment, the second laser sequence follows within about 30millisecond (msec) to about one minute, or from about 20 msec to abouttwo minutes, or from about 10 msec to 1 second. In another embodiment,the second laser sequence follows within about two to about fiveminutes. In yet another embodiment, the second laser sequence followswithin about five to about fifteen minutes. In a further embodiment, thesecond laser sequence follows within about fifteen to about thirtyminutes.

[0042] In a further embodiment, there may be a delay sufficient to allowfor a desired primary biological inflammatory response of several days.One specific, non-limiting example of an extended delay to allow for aprimary biologic response is primary sensitizing treatment using eithersclerosing injection or light irradiance of an unwanted area of legveins insufficient in itself to eradicate this area of leg veins. Thistreatment is followed in a period of 2 to 3 days with a secondary lightirradiance which is amplified in its response sufficient to give vesseldisappearance (treatment). Without being bound by theory, vesseldisappearance is due to the primary subthreshold induced inflammatoryresponse. In this example sclerotherapy injection with hypertonic salinemay be used as an example of primary treatment, with secondary delayedtreatment being irradiance with infrared laser use at 1064 nm, with apulse width of about 12 to 16 milliseconds, with fluences of use ofbetween about 70 to 130 joules, as an example.

[0043] For example, primary treatment using either sclerosing injectionor light irradiance of an unwanted area of leg veins, is followed in aperiod of 2 to 3 days with a secondary light irradiance at the treatmentwavelength, which is amplified in its response by reason of the primaryinflammatory response. In this embodiment the second laser sequence ofpulsed laser light in the yellow to red lengths (treatment wavelength),may follow a primary laser irradiance of infrared emission (sensitizingwavelength). This sequence may be utilized, for example, in thetreatment administered to the neck and or chest for improvement in bothtextural and coarser lines within the skin.

[0044] In one specific, non-limiting example, the primary sensitizinglaser sequence of infrared laser light is between from about 690 nm toabout 1520 nm, and the pulse duration is from below about 1 msec toabout 20 msec. In this embodiment, the treatment laser sequence utilizespulsed visible laser light in the yellow to red wavelengths. In onespecific, non-limiting example, the visible laser light is between about400 to about 700 namometers, or from about 500 to about 600 nanometers,and the pulse duration is from about a half of a millisecond to aboutseveral milliseconds. In one the embodiment, the pulse duration is froma range of about 250 nanoseconds up to about 100 milliseconds. One ofskill in the art can determine the appropriate pulse duration. Ingeneral, the duration is from about a half of a millisecond up to about40 milliseconds.

[0045] The treatment wavelength is a visible wavelength laser emission,or an intense pulsed light emission, pulsed over the same treated skinsurface area as that of the primary infrared laser treatment. Withoutbeing bound by theory, this second irradiance is not targeted to, orabsorbed by, the same chromophore as the first irradiance. Thus, in oneembodiment, the second treatment irradiance is targeted to, and absorbedby, the dermal vasculature. The dermal vasculature has been enhanced inits laser visibility of absorption of energy, by reason of the primaryinfrared laser irradiance being absorbed nonspecifically by the watercontent of the dermal collagen. Accompanying the absorption is therelease of heat and secondary dermal vasodilitation and inflammation.Without being limited by theory, the effects of the absorption of thissecondary visible light laser treatment into the dermal enhancedvasculature is the release of inflammatory mediators that begin aprocess of restoration of the skin and reversal in particular of thephoto-aging process.

[0046] Thus, in one embodiment, the primary dermal irradiance with thesensitizing wavelength is performed with the use of a more infraredbiased cut off filter. In one specific, non-limiting example theinfrared biased cut-off filter is a 755 nm or 695 nm cut-off filter,which allows the passage of light between the cut of 755 nm or 695 nm toabout 1200 nm.

[0047] In one specific, non-limiting example, the infrared biasedcut-off filter is a 755 nm or 695 nm cut-off filter, which eliminatesmore hemoglobin specific shorter wavelengths, and which still allows thepassage of light of a spectrum between the cut of 755 nm or 695 nm up to1200 nm. Without being bound by theory, this light is captured in thewater and pigmented chromophore content of the collagen containingdermis of the skin. The capture of this energy transfers heat into thecollagen layer, and results in vasodilation of smaller blood vesselswithin this skin area. A second intense pulsed light treatment then isperformed within minutes of the first. In one embodiment this secondtreatment uses cut off filters which allow light which is preferablyhemoglobin absorbed to pass through. These cut off filters often willrange from 515 nm to 590 nm, and thus allow emission of light of greaterthan 515 nm or 590 nm. With these cut off filters the light of use is ofshorter pulse widths of between 2 to 5 milliseconds. In one embodiment,this second treatment uses shorter cut off filters of 515 nm, 550 nm, or570 nm and shorter pulse widths of a few milliseconds.

[0048] In one specific, non-limiting example, the sensitizing infraredirradiance of the dermis may be achieved by Nd:YAG laser emissions ofeither about 1320 or about 1040 nm. Without being bound by theory, thislight is captured in the water and pigmented chromophore content of thecollagen containing dermis of the skin. The capture of this energytransfers heat into the collagen layer, and results in vasodilation, andan enhanced secondary light capture target of smaller blood vesselswithin this skin area. The second pulse of light, the treatmentwavelength, may then be targeted to the now enhanced vascularchromophore. This second treatment light emission may be irradiance withnoncoherent intense pulsed light as described above or of a coherentlaser light emission as described above, both of which are targeted tohemoglobin absorption in the now enhanced dermal microvasculature.

[0049] Without being bound by theory, this light is captured by thedermal vasculature that has been enhanced. Thus, the benefits of thistreatment are two fold: (1) there has been a double reparative stimulusboth of dermal damage and microvasculature damage; (2) there has beenenhanced microvasculature damage, and by reason of this enhancement,enhanced stimulation of repair. Thus a method is disclosed hereinwherein a sensitizing wavelength of light is applied to an area of theskin, followed by a treatment wavelength of light that is a shorterwavelength than the sensitizing wavelength.

[0050] The application of these two wavelengths can be separated by abrief recovery time period (see above). The application of both thesensitizing wavelength of light and the treatment wavelength of lightresults in a change of a physical property of the skin. Without beingbound by theory, this process is additive not only by reason of theenhanced vascular chromophore response, but also because reparativeresponses to injury are multifold, both dermal absorption of infraredlaser energy treatment and stimulation of a collagen reparativeresponse, as well as an enhanced secondary irradiance and by reason ofsmall domain blood vessel absorption of energy a separately stimulatedskin repair by reason of injury to these same smaller in size bloodvessels.

[0051] In one specific, non-limiting example, the methods and devicedescribed herein can be used to treat unwanted body hair. In thisembodiment, primary treatment of body surface area designated for hairremoval is first begun with the use of sensitizing wavelength emittedfrom a scanned Alexandrite laser, of about 755 nm, for about 2 to about80 milliseconds pulse width. Without being bound by theory, this firstirradiance is targeted to the hair follicle itself, with the targetwithin the hair follicle being chromophore pigmentation. The energy ofthe first sensitizing irradiance is captured by the darker pigmentwithin the hair follicle, and this energy is transferred as heat energy.The energy destroys the hair follicle and vasodilates the smalldimensional blood vessels that surround and nourish the follicle. Asecond treatment wavelength from a coherent visible light source isapplied to the skin following within minutes of the completion ofsensitizing irradiance. Without being bound by theory, due to thesecondary vasodilatation, this treatment wavelength can be targeted to,and be absorbed by, the small blood vessels surrounding the hairfollicle, and thus remove these vessels.

[0052] The gain in effective treatment (e.g. hair removal) is a severalfold increase, as compared to untreated skin. This method results inadditive damage to the hair follicle, and more effective hair removal.In addition, there is a greater range of hair color response.Specifically, energy absorption by very light colored hair may beminimal, but by enhancing the visibility of small domain blood vesselsaround the hair follicle, the secondary laser treatment may well targethair of very light to minimal color.

[0053] Filtered intense pulsed light may be used in a similar manner byusing pigmented hair treatment parameters initially. In one embodiment,a sensitizing wavelength is applied of about 645 nm or about 695 nm(using a cut off filter). The sensitizing wavelength is used with achain of pulses of between 5 to 7 msecs, with minimal separation of 10msecs. A secondary treatment pulse follows within minutes. This secondtreatment pulse uses a cut off filter of much shorter wavelength, suchas about 550 nm or about 570 nm and a shorter pulse width of about 2 toabout 4 msecs. Without being bound by theory, this second treatmentpulse irradiates the secondarily dilated perifollicular vascular bed,and enhances or causes hair removal due to the damage and destruction ofthis vascular targeted chromophore.

[0054] Additional factors can be used to produce primary targetchromophore enhancement; primary target chromophore enhancement does nothave to be achieved by light irradiation alone. An example of this isthe use of primary microabrasion of the skin surface to achieve, in theprocess of particle microabrasion, a secondary deeper dermal response oferythema. The induced dermal dilation of microvasculature then becomesan enhanced chromophore target for visible light, either a coherentlaser source of light, or a noncoherent source of light such as intensepulsed filtered light. Examples of this process include the rejuvenationof the areas of the chest and neck, or arms and shoulders. These areasare primarily treated with superficial microabrasion to induce a finedermal erythema, in order to dilate the dermal vasculature. Immediatelyfollowing this primary procedure, irradiance with intense pulse filteredlight is used as a sensitizing wavelength, with settings, for example,of about 515 nm, or about 550 nm, or about 590 nm, using a cut offfilter. In this procedure pulsewidths of between about 2 to about 5milliseconds are used. A chain of either a monopulse of light or a chainof pulses separated by only variables to allow for thermal relaxation ofthe epidermis. Thus, an emission of either a single pulse of noncoherentintense pulsed light or a train of pulses separated by an appropriateinterval to allow for thermal relaxation of the pigment containing skinsurface, can be utilized. These intervals between pulses usually rangefrom between about 10 to about 40 milliseconds but may be longer forpatients of darker skin color. This process increases the capture ofthis irradiated fluence by the dermal vasculature, which has beenenhanced, vasodilated by the primary process of surface microabrasion.

[0055] In another embodiment, methods are disclosed herein to enhancepigmentation removal. One specific, non-limiting example is applicationof a therapeutically effective amount of a sensitizing irradiance with acoherent light source, such as an Alexandrite laser, emitting anirradiance of about 755 nm. In one example, this is of short pulse widthsuch as about 10 to about 50 nanoseconds pulsewidth. In one specificnon-limiting example, the primary sensitizing irradiance is of a pulsewidth between about 10 to about 100 nanoseconds. Without being bound bytheory the light is captured in the pigmented melanosome choromophorewithin the skin surface area of pigmentation. The immediate response tothis sensitization is often an intensification of the pigmented area dueto inflammation and possible pigment darkening.

[0056] The first sensitizing irradiation is followed by a secondtreatment irradiation of both longer pulsewidth of several millisecondsand of a wavelength, which can be either specifically targeted to apigment or is more vascular targeted (due to the induced inflammatoryresponse). The secondary treatment follows within minutes after thefirst treatment. The secondary treatment can be with a coherent lightsource or with a non-coherent light source. In one embodiment, thenon-coherent light source is the use of intense pulsed filter light.Intense pulsed filter light includes treatment with a cut off filter ofabout 550 to about 590 nanometers, and pulse widths of between about 2to about 5 milliseconds. Either single or chained pulses can be used,allowing for thermal relaxation times of about 10 to about 40milliseconds.

[0057] As shown in FIG. 19, a system, including an apparatus generallyindicated at 90, is of use for carrying out the described methods. Thesystem includes a controller 100 for controlling the sequence ofemissions from two light sources 110 and 120, such that first lightsource 110 and second light 120 source can be illuminated sequentially.In one embodiment, controller 100 also controls the wavelength emittedfrom light sources 110, 120. The first light source 110 is configured toprovide a therapeutically effective amount of a sensitizing light flux;and a second light source 120 is configured to provide a therapeuticallyeffective amount of a treatment light flux. The first and the secondlight sources can emit either coherent or non-coherent light. An opticalsystem 130 directs the light emitted from light sources 110, 120 to aregion 140 of the skin to be treated.

[0058] In one embodiment, first light source 110 emits infrared light,and is thus an infrared laser source. Infrared light sources include,but are not limited to an Nd:YAG laser. One of skill in the art canreadily ascertain a suitable infrared laser source of use. For example,suitable laser sources are, but are not limited to, the Vasculite laser™at a wavelength of 1064 nm, the Cool Touch Laser™ (either the CoolTouchI™, see U.S. Pat. No. 5,820,626, or the CoolTouch II™, see U.S. Pat. No.5,967,123, CoolTouch Corporation, Roseville, Calif.) at 1320 and 1540nm, and the Arameis erbium glass laser. In a further embodiment, secondlight source 120 emits intense pulsed light. One of skill in the art canreadily ascertain a suitable infrared source intense pulsed light.

[0059] In one embodiment, second light source 120 is a pulsed dye lasersource. Suitable pulsed dye laser sources include, but are not limitedto, the Photogenica V™ and V Star™ lasers (e.g. see U.S. Pat. No.4,364,015 and U.S. Pat. No. 6,045,548, Cynosure, Inc. Chelmsford, Mass.)with use at both 585 and 595 nm. The second light source can also be anintense pulsed light source. These pulsed light sources include, but arenot limited to, the Photoderm Multilight™ (e.g. see U.S. Pat. No.5,683,380 and U.S. Pat. No. 5,720,772, ESC/Sharplan (Lumenis), Norwood,Mass.) with spectral band of emission of filter intense pulsed light ofbetween 515 nm and 1200 nm.

[0060] In one embodiment, a least one controller 100 is provided thatcontrols the first light source. This controller can be a computerizedsystem, or can be a manual system (e.g. a switch). The controller cancontrol both the first light source 110 and the second light source 120.Alternatively, more than one controller can be provided so that thefirst light source is controlled independently form the second lightsource.

[0061] In one embodiment, an optic system is provided 130 for deliveringlight to the skin. A single optic system can be provided that directsthe light from both the first light source 110 and the second lightsource 120. In an alternative embodiment, more than one optic system canbe included for directing light the light emitted by the light sources110, 120. In one specific, non-liming example a first optic systemdirects the light from the first light source and a second optic systemdirects the light from the second light source to the skin.

[0062] The skin is affected by the devices and their methods of usedisclosed herein to apply both the sensitizing and the treatmentwavelength to the skin. The list of parameters that are altered usingthis process, and are considered indicative of a lessening and therein areversal of the aging process, are a decreased in textural lines,coarser lines, or a change in skin laxity or skin tightness. Inaddition, the evenness of color of skin, observed with lessening of sunrelated pigmentation (i.e. dyschromic pigmentation) can be affected.Furthermore, skin exaggerated vascularity (such as telangiectasias andblush erythema) can be lessened, and the observed qualities ofsmoothness, softness, clarity luster, and brightness of skin can beimproved

[0063] Without further elaboration, it is believed that one skilled inthe art can, using this description, utilize the present invention toits fullest extent. The following examples are illustrative only, andnot limiting of the remainder of the disclosure in any way whatsoever.

EXAMPLES Example 1 Experimental Use: Clinical Subjects

[0064] Several subjects were selected who had difficulties with brownage spots, uneven skin color, facial blood vessels, skin roughness, fineline and wrinkles, pore size and blush tone, and rosacea. Fifty-sevenpatients completed a sequence of five treatment sessions using pulsedlight and infrared laser treatment. The sequence of five treatmentsessions was performed between three and six week intervals. Prior tothe treatment, ElaMax 5% cream was applied to the skin, followed by 1320Nd:YAD laser treatment to the selected facial areas. The infrared lightwas applied using a 1320 Nd:YAD laser with linked dynamic cooling (CoolTouch Termescent laser system). A coolant interval of 20 msecs with adelay of 10 msecs was used. Fluences were adjusted to achieve apost-laser pulse skin temperature elevation of 40° C. The areas ofselect infrared laser treatment were periorbit, perioral, and selectedareas of the forehead, cheek rhytides, and acne scars.

[0065] After the 1320 Nd:YAD laser treatment, filtered intense pulsedlight was applied to the entire surface of the face (full facialtreatment). Intense pulsed light was applied from a non-coherent flashlamp light source. The full facial application of light was over theareas of prior infrared laser treatment and over areas that had notspecifically been treated before but where qualities of change would betextural. Cut off filters used between 550 and 590, with sequences oftwo pulses. The pulse width was between 2.4 and 5 msec. Shortercompression pulses of 2.4 msec were associated with purpurae. Longerpulse width settings (between 3 and 5 msec were initially used.Variables were adjusted and incremented for each treatment session, inorder to achieve an endpoint of transient erythma, lasting several hoursto overnight. Bruising was avoided by longer pulse width settings.Fluence settings ranged from 30 joules and were pulse width dependent.

[0066] The areas of select infrared laser treatment were the areas ofgreater line changes. Many of these line changes were lines ofhyperdynamic expression.

[0067] Patients were asked to give a subjective judgement as to theirresponse to treatment in a survey. Thirty-two patients completed survey.

[0068] A high subjective post treatment response was to skin texturalqualities of both lessened blush tone erythema, telangiectasias, andphotolentiginous solar pigmentation. This was seen as evenness of colortone, and described as increasing clarity of skin color. Increased skintonal textural qualities as well as lessening of more defined periorbitand perioral deeper rhytides was seen, suggestive of an overall skintightening response. Within the study group there were no adverseeffects, or increased morbidity.

[0069] The results of the overall ratings of improvement in the skin areshown in FIG. 9. The results of the survey on facial lines are shown inFIG. 10. The results of the survey on rosacea are shown in FIG. 11. Theresults of the survey on blush tone are shown in FIG. 12. The results ofthe survey on facial blood vessel are shown in FIG. 13. The results ofthe survey on skin roughness are shown in FIG. 14. The results of thesurvey on skin color are shown in FIG. 15. The results of the survey onbrown age spot are shown in FIG. 16. The results of the survey on poresize are shown in FIG. 17.

Example 2 Exemplary Protocol

[0070] In order to treat facial widespread sun-induced textural linechange the following protocol is utilized. Primary treatment is infraredlaser irradiance. This irradiance is to selected areas of more discreteline changes, such as around the mouth lines or around the eye lines, oris a full face application. An example of infrared laser irradiancetreatment would be the use of the CoolTouch™ laser.

[0071] The treatment begins with cleansing of any prior existent skinemollients or lotions. Treatment is initiated with the CoolTouch™ I withsettings of coolant spray duration of 20 msecs, delay of 30 msecs, with18 to 20 joules with temperature measurement not to exceed 45 degrees.Alternatively, treatment with the upgraded Cool Touch II™ system isinitiated with settings in a precool (i.e. coolant pulse first withlaser pulse subsequent), mode of a coolant spray duration of 20milliseconds (msecs), with fluences of between about 14 to 18 joules. Atemperature monitored endpoint of between 40 to 45 degree Centigrade isachieved (temperature elevation). An accompanying endpoint is atransient but apparent skin erythema.

[0072] Over areas of more discrete line involvement at least twopatterns of infrared laser irradiance are performed. With the Cool TouchII™ a third pattern of infrared laser irradiance is performed but in apost cool mode. Thus, a laser pulse is administered first with a coolantpulse post laser pulse. The settings are for a duration of coolant sprayof 30 msecs with laser pulse fluences of 10 to 18 joules. Uponcompletion of infrared laser irradiance of the selected zones oftreatment (i.e. peri-oral, peri-orbital or full face application, or asin the subsequent example the neck area for reasons of treatment oftextural lines of skin aging change), a fine erythema is present as anappropriate endpoint of this first phase of treatment application.

[0073] The second phase of irradiance, following completion of theprimary irradiance (see above), is treatment with intense pulse light.One specific, non-limiting example of a laser of use is the MultiLight™.Visible light irradiance is applied over the just completed areas ofprimary infrared irradiance treatment. In this secondary irradiance apresent but fading erythema from the primary irradiance can still bepresent. The selected parameters of intense pulsed light treatment willvary as to the patient's skin color and pigmentation. In one protocol,settings of treatment using intense pulsed light is a doublet pulsecomposed of a primary T1 pulse of 3 msecs, and T2 pulse of4 msecs with adelay setting of 10 msecs, with a cut off filter inserted of 550 nm withfluences of between 32 to 40 joules. In another protocol, longersettings of between 4 to 6 msecs doublet pulses are used and lower cutoff filters are used of 515 nms. The desired endpoint clinicallyobserved as to treatment is a fine erythema. The treatment is appliedover the areas of primary infrared laser irradiance.

Example 3 Treatment of Textural Lines on the Face and Neck

[0074] Another exemplary protocol example would apply to the treatmentof textural lines on the face and neck. Primary irradiance is infraredirradiance using either the parameters of the above described CoolTouchI or II protocol over an area of about 120 mm². Alternatively infraredirradiance erbium glass laser irradiance is used with triplet pulses toquintuplet pulses with linked cooling with fluences of between 10 to 12joules, or about 0.08 to about 0.1 joules/ mm². The secondary irradiancewith visible light is provided with treatment with the V Star Laser™(see above) or Photogenica Laser™ (see above) at settings of 585 nm, 0.5msecs pulse duration, and with a 10 mm spot size, fluences of between2.5 and 3.0 joules (or about 0.02 to about 0.25 joules/mm²). Care istaken to avoid a purpuric or bruising response. In one protocol, twosequences of laser pass patterns in this manner are used over thetreatment field.

[0075] Results of improvement of textural and coarser lines, is measuredboth objectively and subjectively by photographic documentation as wellas laser profilometry. An important determinant of response isobservation over time to extend at least 6 months after completion ofthe series of active treatment.

Example 4 Clinical Results

[0076] In order to compare the additive advantages of primarysensitizing treatment with an infrared laser irradiance in combinationwith a closely sequenced treatment irradiance with a visible lightemission pulsed dye laser the following study was performed. The resultsobtained were compared with irradiance with pulsed dye laser treatmentalone.

[0077] The right and left half neck areas to be treated were randomizedas to either combined treatment or pulsed dye laser only treatment. TheCool Touch II™ laser (see above) was used as an infrared source laserfor irradiance of the randomized right or left neck areas. Settings wereset for irradiance at 14 to 18 joules, at a pre-cool duration of 20msecs, with a post-cool irradiance at 14 to 16 joules at a post coolduration of 30 msecs. A fine but short lived erythema was sought as aclinical endpoint of sensitizing treatment with post treatment peaktemperature elevations not in excess of 43 degrees centrigrade.

[0078] Immediately post completion of randomized right or left neckinfrared irradiance, confluent, both right and left neck areas weretreated with 585 nm pulse dye laser visible light irradiance, at 0.5msecs pulse duration, with a 10 to 12 mm spot size at 2.5 to 3.0 joulesof energy. Three independent treatment sessions were given at 4 weekintervals, with the above observation as to judged differences inbilateral treatment response as observed at 5 months post initiation ofthe first treatment.

[0079] The results shown in FIG. 18 reflect the cumulative scores as toimprovement of textural lines and limited coarser line change of judgedpatient improvement both objectively and subjectively. Previous resultshave demonstrated that infrared laser irradiance alone has not givenequivalent scores of clinical improvement. Similarly, equivalent scoresof textural improvement were documented with the pulse dye laser onlytreatment in a comparison study of randomized right and left lateralcheek and face pulse dye laser treatment versus no treatment. Nopatients who objectively or subjectively showed improvement on thepulsed dye laser treated half neck area demonstrated an effect greaterthan the combined treatment side.

[0080] This results from this clinical study demonstrates thesyngergistic effect seen with combined primary dermal infraredsensitizing irradiance with secondary visible light treatmentirradiance. In this clinical example the primary sensitizing irradiancewith the Cool Touch II™ infrared laser gave a synergistic amplificationof a beneficial clinical response when followed in close sequence by VStar™ (see above) pulsed dye visible light irradiance.

Example 5

[0081]FIG. 4 is a schematic representation of a pulse of visible lightenergy on the skin. The energy can be emitted either from a laser orintense pulsed light source. This light energy reaches into the collagenlevel of the skin and is captured by smaller blood vessels, which wereaugmented by a first infrared light energy pulse. The blood vessels haveincreased in size and become more accessible to absorbing visible lightenergy, due to the energy of the first infrared light energy pulse(which is absorbed by water, and thus indirectly augments the bloodvessels within the collagen level of the skin). The second visible lightenergy pulse is configured to be absorbed by the hemoglobin (“red”color) within the vessels enhanced by the first light energy pulse.Therefore, the second visible light energy pulse has been effectivelyamplified by the first complementary infrared laser light energy pulse.Damage to the vessels with the collagen layer of the skin can theninitiate an inflammatory response that therapeutically stimulatescollagen remodeling and wrinkle removal.

[0082]FIG. 8 is a schematic representation which shows how the effectsare amplified by a subsequent pulse of visible light energy that is nottargeting hair pigment or the hair gland directly, but is destroying thesmaller blood vessels around the hair gland. These vessels were toosmall to be selectively treated before the effects of the first lightpulse configured for the color of hair. The first light pulse enhancedthe size of the vessels and made them selectively susceptible to thesecond light energy pulse, which is configured to the color and size ofthese vessels essential to the nourishment of the hair gland.

[0083] In view of the many possible embodiments to which the principlesof our invention may be applied, it should be recognized that theillustrated embodiment is only a preferred example of the invention andshould not be taken as a limitation on the scope of the invention.Rather, the scope of the invention is defined by the following claims. Itherefore claim as my invention all that comes within the scope andspirit of these claims.

We claim:
 1. A method of altering a physical property of a region ofskin, comprising: applying a therapeutically effective amount ofsensitizing light to the region, so that light energy is absorbed by theskin; and applying a therapeutically effective amount of treatment lightto the region, wherein the treatment light is of a wavelength orwavelengths shorter than a wavelength or wavelengths of the sensitizinglight; wherein the application of the effective amount of thesensitizing light enhances an effect of the treatment light in alteringthe physical property of the region of the skin.
 2. The method of claim1, wherein the sensitizing light is infrared light.
 3. The method ofclaim 1, wherein applying a treatment wavelength of light to the regioncomprises applying coherent light to the region.
 4. The method of claim1, wherein the treatment light is a visible light.
 5. The method ofclaim 1, wherein the sensitizing light is of a wavelength from about 600nm to about 1320 nm.
 6. The method of claim 1, wherein the sensitizinglight is of a wavelength from about 1040 nm to about 1320 nm.
 7. Themethod of claim 6, wherein the sensitizing light is of a wavelength ofabout 1320 nanometers.
 8. The method of claim 1, wherein the treatmentlight is intense pulsed light.
 9. The method of claim 8, wherein theintense pulsed light is pulsed visible light.
 10. The method of claim 8,wherein the treatment light is of a wavelength of about 400 to about 700nanometers.
 11. The method of claim 10, wherein the treatment light isof a wavelength of about 500 nanometers to about 600 nanometers.
 12. Themethod of claim 1, wherein applying the therapeutically effective amountof the treatment light follows completion of applying thetherapeutically effective amount of the sensitizing light.
 13. Themethod of claim 1, wherein altering the physical property comprisesremoval of hair.
 14. A method of altering the appearance of a region ofskin, comprising: applying a therapeutically effective amount of lightenergy to the region of skin wherein the light energy applied has awavelength of about 695 nanometers to about 1200 nanometers; applying atherapeutically effective amount of intense pulsed light to the regionof the skin, wherein the intense pulsed light is applied within minutesof the light energy, wherein the intense pulsed light applied has awavelength of about 500 nanometers to about 600 nanometers; wherein theapplication of the light energy and the intense pulsed light results ina change in a physical property of the region of the skin; and whereinthe application of light energy results in an erythema of the region ofskin that enhances susceptibility of the region of skin to thetherapeutically effective amount of intense pulsed light.
 15. The methodof claim 14, wherein the intense pulsed light has a wavelength of lessthan 550 nm.
 16. A system for treating skin, comprising a first lightsource configured to provide a therapeutically effective amount of asensitizing light flux; and a second light source configured to providea therapeutically effective amount of a treatment light flux; whereinthe first light source and the second light source can be illuminatedsequentially, and the second light source is of a shorter wavelength ora range of shorter wavelengths than the first light source.
 17. Thesystem of claim 16, further comprising at least one controllerconfigured to selectively activate either the sensitizing light flux orthe treatment light flux.
 18. The system of claim 16, further comprisinga controller configured to selectively activate the sensitizing lightflux and the treatment light flux, wherein the treatment light flux isactivated following multiple consecutive pulses of the sensitizing lightflux.
 19. The system of claim 16, further comprising at least oneoptical system to deliver to the skin the sensitizing light flux, thetreatment light flux, or both.
 20. The system of claim 16, wherein thefirst light source emits infrared light.
 21. The system of claim 16,wherein the second light source emits intense pulsed light.
 22. Thesystem of claim 16, wherein the first light source and the second lightsource are illuminated sequentially wherein the treatment light flux isactivated following multiple consecutive pulses of the sensitizing lightflux, and the sensitizing light flux is activated following multipleconsecutive pulses of the treatment light flux.
 23. The system of claim16, comprising a means comprising at least one controller and at leastone optical system operable to direct sequentially first the sensitizinglight flux and then the treatment light flux to a selected region ofskin.
 24. The system of claim 23, wherein the first light source emitsinfrared light and the second light source emits intense pulsed visiblelight.
 25. The system of claim 23, wherein the second light source isilluminated only after illumination with the first light source fortreating the skin is completed, and the first light source is notilluminated after the second light source is illuminated.